Patently Apple:

Today the US Patent & Trademark Office published a patent application from Apple that relates to displays having a substrate with a visually imperceptible texture that provides tactile sensations varying with an object contacting the surface. Apple is considering applying a new finish on displays for Macs and iDevices that acts as an added protection layer with a different texture to the glass. The glass may feel smooth to the touch but slightly rougher with a little drag when using it with an Apple Pencil.

Not clear if this difference in feel is what they were going for in the first place, or a side product of the finish. What would really be cool is if there was a way to control that texture electronically, adjust it based on context.

Fascinating.